giant giant tortoise reptile shell tortoise animal armoured carapace foot Greece Greek head marginated tortoise natural nature plates spring Testudo marginata black brown browns colors colours contours cover dips exterior grooves hard horny plates layers lines outlines pointed points protection rough shapes shelter sides solid strength strong textures tips tortoise shell tough white feet green walking big pet wild Asia cute turtle animals cold blooded eco exotic pet forest Geochelone elegans herbivorous Indian Star Tortoise jungle wild animal zoo moss terrapin water